Steel producing plant with one or several electric arc furnaces

ABSTRACT

A multi-bay steel producing plant that has one or more electric arc furnaces arranged on a floor and surrounded by a closed cell. The cell has a portion of its wall that is movable to allow for access to the furnace, and is made of sound-absorbing materials to deaden the loud noises emanating from the furnace. An exhaust fan and pipe are provided in the cell to rid the interior of the cell of exhaust gases. A transfer vehicle for transporting the ladle containing the steel charge is movable on tracks located below the cell and a taphole of the furnace.

United States Patent Wolters 1 Oct. 21, 1975 [54] STEEL PRODUCING PLANT WITH ONE OR 3,788,6l9 l/l974 Dortenzo 266/13 SEVERAL ELECTRIC ARC FURNACES 3,806,622 4/1974 Marclmer l3/l 3,809,376 5/l974 266/l6 Inventor: Gunter Wolters, Duisburg, Germany Assignee: Gutehoffnungshutte Sterkarade Aktiengesellschaft, Oberhausen-Sterkarade, Germany Filed: Mar. 20, 1974 Appl. No.: 453,073

Foreign Application Priority Data Mar. 20, I973 Germany............................ 2313660 US. Cl 266/13; l3/l lnt. Cl. C21B "/10 Field of Search.,.............. 266/13, l6, l7; 13/1;

References Cited UNlTED STATES PATENTS 6/l973 Lebeau l8l/33 K Primary Examiner-Roy Lake Assistant ExaminerPaul A. Bell Attorney, Agent, or FirmToren, McGeady and Stanger [57] ABSTRACT A multi-bay steel producing plant that has one or more electric arc furnaces arranged on a floor and surrounded by a closed cell. The cell has a portion of its wall that is movable to allow for access to the fur nace, and is made of sound-absorbing materials to deaden the loud noises emanating from the furnace. An exhaust fan and pipe are provided in the cell to rid the interior of the cell of exhaust gases. A transfer vehicle for transporting the ladle containing the steel charge is movable on tracks located below the cell and a taphole of the furnace.

3Claims, 2 Drawing Figures U.S. Patent 0.21,197s Sheetl0f2 3,913,898

U.S. Patent 0a. 21, 1975 Sheet 2 ot'2 3,913,898

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STEEL PRODUCING PLANT WITH ONE OR SEVERAL ELECTRIC ARC FURNACES BACKGROUND OF THE INVENTION The present invention concerns a steel producing plant with one or several electric arc furnaces.

Plants of this kind are oneor multi-bay constructions. In case of one-bay constructions, the casting ar'ea borders in longitudinal direction the furnace area. The steel run-off of the furnace ispoured into a ladle which i's'positioned under the furnace or hanging in a crane. The crane running overthe furnace takes the ladle off, after the run-off, in order to transport it to the casting a'rea.

In case of-two-bay or multi-bay constructions, there is normally-a furnace hall and separated from the latter a special casting hall. In this case the electric arc furnace is positioned in a way such as to let the run-off opening'of the furnace extend into the casting hall. In case such an'installation is equipped with special devices for continuous charge, the latter are positioned within the furnace hall.

The general and most outstanding disadvantage of these plants is the fact that scrap melting can only be effected under great and important noise. There is a direct relation between noise display and the furnaces melting capacity.

Additional to the above mentioned noise display, there is an important smoke display during the melting period. In many cases it's true that with the well known electric arc furnaces the rising smoke gasesget sucked off from the furnace room. It is however very difficult to regulate the pressure within the furnace interior be cause of the rising gas and the gas exhaustion in a way to preventdust-charged smoke gas from penetrating within the furnace hall.

SUMMARY OF THE INVENTION The claim of the present invention isto avoid the above mentioned disadvantages. Thusthe invention is based on the task of ameliorating the environmental conditions within and outside the steel producing plant.

According to this invention, this amelioration is effected by the fact that the electrical arc furnace gets surrounded, or walled by a closed cell. This cell is positioned on the furnace stage; it is equipped with a suction pipe and provides an inner underpressure important enough to suck-off the arising smoke gases; the walls of the cell consisting of a sound deadening material. By means of this cell, the sound level in the direct proximity of the furnace within the steel mill as well as in the surroundings of the steel producing plant gets reduced considerably. The smoke gases can be suckedoff from the cell very easily without any necessity of regulating the furnace room pressure. The attendants screw operating the furnace are no loner as in former times affected by those unpleasant environmental influences. The annoyances of the steel mill surroundings are therefore reduced to a supportable extent.

Another claim of the present invention is the fact that part of the cell walls are laterally movable. The travel- -ling part of the cell preferably consists of the vertical wall within the range of the charge crane, and of the upper part of the cell covering in a width of approximately the furnace basin. The erection of such a partially travelling cell is very simple. The cell fulfills its task to its full extent during the very period of important and extreme environmental loads and encumbrances. During all periods in which the furnace must be easily accessible, such as for instance for scrap charging, change of electrodes, repairing and the like, the cellule can be widely opened without any disadvantageous consequences.

As there is smoke gas display also during the run-off period, the cell should also cover the run-off opening of the furnace and the ladle receiving the steel. So it is proposed to install tracks between the casting hall and electrical arc furnace on the level of steel works below the cell, i.e. tracks for a transportation lorry for transportation of the ladle under the run-off opening of the furnace. During the run-off period, the ladle is located on a steel transport lorry below the cell; after the runoff process and afte'rtransportation to the casting hall, the ladle gets rendered tothe casting crane.

' By using the cell,the installation according to the present invention enables the construction of a special raw material supply hall or bay separately from the furnace bay.

BRIEF DESCRIPTION OF THE DRAWING The following construction model and drawing will give some detailed specification as to the present invention:

FIG. 1 shows the horizontal plan of a are furnace plant.

FIG. 2 shows the cutting II ll partially in section according to FIG. I.

DETAILED DESCRIPTION OF THE INVENTION The described steel mill consists of the furnace bay (hall) 1 and the casting bay 2. Inside. the furnace bay, there are several electrical arc furnaces 3 positioned in a row, one of which is shown in detail. The electrical arc furnace 3 consists of the furnace basin 4 and cover 5, through which the electrodes 6 are conducted. There are main supply cables 8 between the electrodes 6 and the transformer 7. The furnace basin 4 is in order to enable discharging tiltable. The steel charge gets discharged by means of the run-off opening 9 into a ladle 10.

The electrical arc furnace 3 is surrounded at a certain distance laterally and on the upper-side by a cell 1 l. The above mentioned distance has to be great enough such as to avoid any hindrance or encumbrance of the normal functions of the furnace; this means that for instance the furnace must be freely tiltable; charging the electrical arc furnace 3 with its cover 5 opened must be possible, when the cell 11 is open; change of electrodes and other kinds of operations must be possible within this distance. Position 5' of the cover 5 shows in FIG. 1, how far the cover 5 has to be moved off. The cell 11 is located on the furnace stage 12. the walls of the cell 11 are made from a sound deadening material, which is partially heat-proof.

In case of several electric arc furnaces, a separate cell can be provided for each furnace. Circumstances permitting, one cell 11 may come to cover several electric arc furnaces.

The cell 11 is provided with a sucker pipe 13, which is connected by means of a connection conduit 14 to a suction fan. The underpressure produced by the fan is sufficient to suck off the dust-containing smoke gases in the furnace area. Any dust is normally extracted from these gases. As for sucking-off the smoke gases only a very slight underpressure of a few mm water column is sufficient, the cell ll not requiring any gas tight construction. There is no disturbance by small quantities of wrong air.

The cell 11 consists of several parts; it consists of a stationary and of a travelling part. The travelling part is within the range of the charging crane l and consists of the vertical wall 16 and the cell cover 17, both of which are approximately cover the width of the furnace basin 4. The cell cover 17, together with the vertical wall 16 form some kind of semi-portal, which travels by means of pulleys [8 or running wheels.

The other parts of cell 1 l, i.e. the opposite longitudinal wall 19, the connecting side walls 20, and the remaining part of the cell cover 2] are stationary. The cell 11 is connected to the furnace stage 12. The travelling parts of the cell 11 are sealed in relation to the stationary parts by means of labyrinth packings or other lining devices.

After opening the semi-portal 16/ l 7 the electrical arc furnace is freely accessible and can be controlled or operated. [t is also possible then to charge the furnace 3 by means of a charging basket or to repair the furnace basin, to change the cover 5 or the change to electrodes 6.

The transformer 7 is located at a side wall 20 of the cell 1]. the supply cables 8 towards the electrodes 6 are therefore only conducted within the cell 11.

The run-off opening 9 of the electrical arc furnace 3 is also located inside the cell 11. Thus the ladle 10 receiving the steel must be placed under the cell 11. For this purpose a transportation lorry 22 is used, which runs on the tracks 23, which are positioned in front of the run-off opening 9 of the furnace 3 just on the ground floor 24. By these means, the smoke gases arising during the run-off processes can also be sucked-off through the cell 11.

Transversely to the furnace bay 1, there is a raw material supply bay 25. In this supply bay there are the storage tanks 26 for the flux. in order to enable normal charging of the electric arc furnace with flux material through the fire-door, a lock-up access 27 is provided in the longitudinal back wall 19 of the cell 11. In case of continuous charging with case materials through the furnace cover 5, this charging is effected by means of a permanent charging device 28; locks 30 are provided in the longitudinal wall 19 of cell 11 for transportation to the charging openings 29.

I claim I. Multi-bay steel producing plant with at least one electric arc furnace mounted on a floor comprising a closed cell surrounding said at least one arc furnace, said closed cell comprising a wall structure consisting of sound-absorbing materials and exhaust means for exhausting the flue gases contained in said cell, a charging crane located above said closed cell, said wall structure of said closed cell comprising a vertical wall and an upper cover in the area of said charging crane, means for movably supporting said vertical wall and said upper cover to allow access to said at least one are furnace while said furnace is enclosed in said cell and to allow the charging of the furnace, a transfer vehicle for transferring the steel contained in a ladle to a subsequent processing station, and track means for allowing the transfer vehicle to move laterally of said cell from a position directly under a taphole in said furnace to the subsequent processing station.

2. The multi-bay steel producing plant according to claim I, wherein said wall structure comprises a stationary portion, said means for movably supporting said vertical wall and said upper cover comprising roller means that permit said vertical wall and upper cover to move relative to said stationary portion, and packing means for sealing said movablemeans from said stationary portion and the floor.

3. The multi-bay steel producing plant according to claim 1, further comprising a raw material supply house arranged directly next to the closed cell, said wall structure of said closed cell comprising a stationary portion and locks formed in said stationary portion for effecting the transfer of the raw material from said supply house to said electric arc furnace. 

1. Multi-bay steel producing plant with at least one electric arc furnace mounted on a floor comprising a closed cell surrounding said at least one arc furnace, said closed cell comprising a wall structure consisting of sound-absorbing materials and exhaust means for exhausting the flue gases contained in said cell, a charging crane located above said closed cell, said wall structure of said closed cell comprising a vertical wall and an upper cover in the area of said charging crane, means for movably supporting said vertical wall and said upper cover to allow access to said at least one arc furnace while said furnace is enclosed in said cell and to allow the charging of the furnace, a transfer vehicle for transferring the steel contained in a ladle to a subsequent processing station, and track means for allowing the transfer vehicle to move laterally of said cell from a position directly under a taphole in said furnace to the subsequent processing station.
 2. The multi-bay steel producing plant according to claim 1, wherein said wall structure comprises a stationary portion, said means for movably support said vertical wall and said upper cover comprising roller means that permit said vertical wall and upper cover to move relative to said stationary portion, and packing means for sealing said movable means from said stationary portion and the floor.
 3. The multi-bay steel producing plant according to claim 1, further comprising a raw material supply house arranged directly next to the closed cell, said wall structure of said closed cell comprising a stationary portion and locks formed in said stationary portion for effecting the transfer of the raw material from said supply house to said electric arc furnace. 